Leukemia is a cancer of the bone marrow, which is the area where our blood cells are formed. In people with leukemia, the bone marrow produces abnormal white blood cells. It develops when blood stem cells become damaged and no longer behave and grow normally. These abnormal — leukemia — cells crowd out the normal, healthy white blood cells, red blood cells, and platelets. This makes it hard for blood to do its work.

The facts

“There are four main types of the disease classified by the cell of origin, the rapidity of growth, and the degree of maturation of the cancer cell: acute lymphocytic leukemia (ALL), acute myelogenous leukemia (AML), chronic lymphocytic leukemia (CLL), and chronic myelogenous leukemia (CML),” explains Dr. Aaron D. Schimmer, a staff physician and senior scientist at the Princess Margaret Cancer Centre, University Health Network, one of the largest cancer research institutes in North America.

“Some of the ways that patients can deal with the psychosocial implications of this kind of disease is through awareness, education, and support.”

ALL and CLL are cancers that arise from abnormal lymphoid stem cells. AML and CML develop from abnormal myeloid stem cells.

Acute leukemias are cancers of immature white blood cells. Symptoms often begin suddenly, developing within days or weeks, and can include severe fatigue, weight loss, fever, and easy bruising and bleeding. Chronic leukemias often develop slowly, over months or even years. At times, patients present with no symptoms: the disease is usually discovered during a routine blood test.

Treatments and innovations

Treatments are tailored depending on the type of leukemia that a patient has. “We have seen tremendous success in the treatment of CML over the last 15 years,” says Dr. Schimmer. “After decades of research into understanding the genetic and molecular abnormalities of CML cells, it was possible to develop a drug that specifically targeted the molecular defect.”

Lessons learned in treating CML have spilled over to other leukemias, resulting in an explosion in targeted therapies for other types of the disease, such as CLL. These targeted medications selectively kill off the leukemia cells with little effect on the normal cells and produce significant responses in patients.
“Even in the areas of acute leukemias, where therapies directed against the specific molecular and genetic abnormalities were lagging a little behind, we’re starting to see the development of targeted therapies that are showing positive results in the early stages,” says Dr. Schimmer. “The future is looking very bright.”

Patient education

A diagnosis of leukemia in any form can be as difficult to deal with emotionally as it is physically. “Some of the ways that patients can deal with the psychosocial implications of this kind of disease is through awareness, education, and support,” says Dr. Schimmer.  

Patients can often find access to support groups through their hospital and there are excellent patient support resources available online through disease-focused charitable organizations and governmental sources. The Leukemia Lymphoma Society and the National Institute of Health, for example, have comprehensive websites offering reliable information for patients.

“Understanding the disease and understanding the course of treatments can also be helpful for patients in these life changing situations,” Dr. Schimmer says.